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Summary of significant accounting policies - Additional Information (Details) (USD $)
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12 Months Ended | |
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Dec. 31, 2012
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Dec. 31, 2011
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| Accounting Policies [Abstract] | ||
| Cash insured | $ 250,000 | |
| Cash balances in bank accounts, uninsured amount | 1,070,000 | 3,200,000 |
| Short-term investments minimum maturity | 3 months | |
| Short-term investments maximum maturity | 1 year | |
| Allowance for doubtful accounts | 154,400 | 96,800 |
| Advertising expense | 187,500 | 86,700 |
| Research and development costs reimbursed by government agencies | $ 126,500 | $ 239,000 |
| X | ||||||||||
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- Definition
Research And Development Arrangements With Government Agencies, Customer Funding To Offset Costs Incurred No definition available.
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- Definition
Short-Term Investments, Maximum Maturity Term No definition available.
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- Definition
Short-Term Investments, Minimum Maturity Term No definition available.
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- Details
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- Definition
Amount charged to advertising expense for the period, which are expenses incurred with the objective of increasing revenue for a specified brand, product or product line. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
A valuation allowance for trade and other receivables due to an Entity within one year (or the normal operating cycle, whichever is longer) that are expected to be uncollectible. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
The amount of cash deposited in financial institutions as of the balance sheet date that is insured by the Federal Deposit Insurance Corporation. No definition available.
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- Definition
The amount of cash as of the balance sheet date that is not insured by the Federal Deposit Insurance Corporation. No definition available.
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